Abstract. The shortwave (SW) radiation budget was computed on a 10 km × 10 km
resolution above FORTH-CRETE AERONET station in Crete, Greece, for the
11-year period from 2000 to 2010. The area is representative of the Eastern
Mediterranean region, where air pollution and diminishing water resources
are exacerbated by high aerosol loads and climate change. The present study
aims to quantify the aerosol direct effect and forcing on the local surface
and atmospheric energy budget. A radiative transfer model was used, with
climatological data from the Moderate Resolution Imaging Spectroradiometer
(MODIS), on board NASA's Terra and Aqua satellites. The instantaneous
radiative fluxes were computed for satellite overpass times at the surface,
within the atmosphere and at the top of atmosphere (TOA). Downward surface
fluxes and aerosol input data were validated against ground measurements.
Output fluxes reveal the direct radiative effects of dust events, with
instantaneous values reaching up to −215, 139 and −46 Wm−2 at the
surface (cooling), within the atmosphere (warming) and at TOA (cooling),
respectively. Mean monthly values show a decreasing trend of the aerosol
direct radiative effect, in agreement with a similar trend in AOT. The
analysis of the contribution of anthropogenic and natural aerosol show major
peaks of natural aerosol direct effect occurring mainly in spring, while a
summer maximum is attributed to anthropogenic aerosol. During their peaks,
anthropogenic aerosol forcing can reach values of −24 Wm−2 at the
surface, 19 Wm−2 in the atmosphere and over −4 Wm−2 at TOA
(monthly mean instantaneous values). The corresponding monthly peak values
for natural aerosol are over −20 Wm−2, 12 Wm−2 and −9 Wm−2.